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Handbook of Water and Wastewater Treatment Plant Operations - Chapter 16

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Bảo vệ lưu vực sông là không chỉ quan trọng đối với con người trong đảm bảo tiếp tục tăng trưởng với số lượng nhưng là rất quan trọng sự sống còn của họ. Đơn giản chỉ cần đặt, bảo vệ lưu vực sông một thách thức mà chúng ta phải đáp ứng. Trong khi nó là sự thật rằng môi trường chương trình bảo vệ tại Hoa Kỳ đã đi một cách lâu dài đối với việc cải thiện chất lượng nước trong quá trình cuối cùng phần tư thế kỷ, tuy nhiên, thách thức vẫn còn nhiều. theo Cơ quan Bảo vệ Môi trường Mỹ. | 16 Watershed Protection Watershed protection is one of the barriers in the multiple barrier approach to protecting source water. In fact watershed protection is the primary barrier the first line of defense against contamination of drinking water at its source. Ideally under the general concept of quality in means quality out a protected watershed ensures that surface runoff and inflow to the source waters occur within a pristine environment. Protecting watersheds is not only critical to humans in ensuring their continued growth in numbers but is critical to their very survival. Simply put protecting watersheds is a challenge that we must meet. While it is true that environmental protection programs in the U.S. have gone a long way toward improving water quality during the last quarter century yet many challenges remain. According to U.S. Environmental Protection Agency EPA as of 1994 nearly 40 percent of surveyed waters in the U.S. remain too polluted for fishing swimming and other uses. The leading causes of impairment found in the survey include silt sewage disease-causing bacteria fertilizer toxic metals oil and grease. 16.1 INTRODUCTION Water regulates population growth influences world health and living conditions and determines biodiversity. For thousands of years people have tried to control the flow and quality of water. Water provided resources and a means of transportation for development in some areas. Even today the presence or absence of water is critical in determining how we can use land. Yet despite this long experience in water use and water management humans often fail to manage water well. Sound water management was pushed aside in rapid never-ending economic development in many countries. Often optimism about the applications of technology e.g. dam building wastewater treatment or irrigation measures exceeded concerns for or even interest in environmental shortcomings. Pollution was viewed as the inevitable consequence of development the price